Climate Overview
The climate in Phnom Penh is hot. The average annual temperature is 29°C and approximately 1431mm of precipitation falls per year. September is the wettest month, receiving around 254mm of rainfall. Phnom Penh is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: April, May, March. The coldest months are January, February, December, when temperatures can drop to 23°C.
Temperature
Phnom Penh sees moderate temperature variation throughout the year, ranging from 23°C to 36°C. April is the hottest month, with daytime highs reaching 36°C and an average of 31°C. January is the coolest month, with minimum temperatures around 23°C and an average of 27°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows.
Precipitation
Phnom Penh is a fairly wet location, receiving approximately 1431mm of precipitation annually, which averages out to around 119mm per month. The wettest month is September, averaging 254mm of rainfall. October and August also tend to see above-average precipitation. The driest month is February, with just 12mm. That's 242mm less than September, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
Phnom Penh is mildly breezy, with an average annual wind speed of 13km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is December, averaging 15km/h, though still comfortable for most outdoor activities. The calmest conditions occur in October, with average winds dropping to 10km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 5km/h gap between the calmest and windiest months.
Seasons
90 days until Summer
It is currently spring in Phnom Penh, which began on March 20, 2026. Phnom Penh is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in April at around 36°C, while the coldest stretch bottoms out in January near 23°C. Summer is next, beginning on June 21, 2026 — 90 days from now.
Spring
Temperatures range from 26 to 36°C. Precipitation is moderate at around 227mm for the season, averaging 76mm per month. Winds are generally light, averaging 12km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 26 to 34°C. Rainfall is heavy, totalling around 511mm across the season with a monthly average of 170mm. Winds are generally light, averaging 14km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 25 to 32°C. Rainfall is heavy, totalling around 623mm across the season with a monthly average of 208mm. Winds are generally light, averaging 12km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 23 to 33°C. Rainfall is relatively light, with around 71mm over the season and a monthly average of 24mm. Winds are generally light, averaging 13km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Monthly Climate Data
The table below shows monthly climate averages for Phnom Penh based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
